1. Field of the Invention
This invention relates to an improved electronic lock for securing goods and areas requiring a high degree of security. More particularly, this invention relates to an electronic lock that can be locked and unlocked electronically.
2. Description of the Related Art
Safes and other secure containers have traditionally used combination locks for controlling and authorizing entry. Conventional locks were mechanical and relied on a person dialing a correct combination on a rotating dial. The rotation positioned mechanical elements within the lock such that dialing the correct combination allowed a locking bolt to release the container door. Proper dial rotation aligned gates in tumblers. Once the gates were aligned, a fence on a fence lever entered the aligned gates. Continued rotation of the dial and tumblers pulled the fence lever and withdrew the bolt.
However, over the years electromechanical locks have gradually replaced the mechanical locks described above. Indeed, electromechanical locks themselves have seen many improvements over the years. The use of sophisticated electronic logic circuitry has enabled the implementation of a series of complex and unique electronic combinations which has made improper entry into secured areas more difficult. When the lock is used to secure entry to a container, the electronic components are typically mounted within a housing inside the container door. The housing contains an actuating device and a circuit board. The electronic key pad transmits a signal to the circuit board, which contains the electronic circuitry that allows the lock to open and close. The keypad is located on the outside of the housing so as to be accessible to the user. A cable typically extends between the keypad and the circuit board for transmitting signals between the two components.
In addition to the electronic circuitry, electromechanical locks include a bolt. The bolt is movably constructed and is coupled to a bolt-displacing device enabling a user to selectively move the bolt into one of at least two end positions by means of the actuating device. The lock is blocked and therefore “locked” in a first end position of the bolt and unblocked or “open” and “unlocked” in a second end position of the bolt. When the user enters the correct combination into the electronic keypad, a signal is transmitted to the circuit board. The circuit board in turn actuates the actuating device, which allows the locking bolt to move to the unlocked position within the housing, thus allowing the user to open the safe door.
There are two types of bolts, rotary bolts and rectilinear bolts. In particular, rectilinear bolt locking devices mount a bolt within a housing for moving between locked and unlocked positions. Thus, instead of pivoting like rotary bolts, linear bolts slide into and out of the locking device housing. When the user enters the correct combination, the lock mechanism releases thus allowing the locking bolt to slide into the housing.
Although known electronic safety locks have proven effective in everyday practical use, there is a need for improvement, particularly with regard to design. In known electronic locks, the interaction of the bolt and the blocking member is mechanically quite complex thus requiring complicated and expensive mounting. In addition, most electronic locks require the consumption of a great deal of energy causing frequent replacement of the power source. When the correct combination is entered, a signal is given to an actuator move the locking mechanism into the open position. The actuator causes the locking mechanism to remain open for a period of time after which the signal to re-lock is automatically triggered. Thus, known electronic locks typically require the consumption of excess energy.